Hydrotreating catalysts prepared from hydrogels

ABSTRACT

This invention relates to a process for preparing highly active hydrotreating catalysts prepared by incorporating an element selected from the group consisting of nickel, cobalt and mixtures thereof, a heavy metal selected from the group consisting of molybdenum, tungsten and mixtures thereof, into a phosphated alumina hydrogel. The final calcined catalysts have surface areas at least about 300 m 2  /g, at least about 20% of the pore volume in pores having diameters greater than about 350 Å and at least about 20% of the pore volume in pores having diameters less than about 70 Å.

FIELD OF THE INVENTION

This invention relates to a process for preparing highly activephosphated alumina hydrogel-derived catalysts.

BACKGROUND OF THE INVENTION

In the catalytic processing of petroleum feedstocks, it is oftendesirable to alter the pore structure of the catalyst in order toaccommodate different types of feeds. For example, when processingfeedstocks with no metals or with a low metals content, it may betechnically and economically desirable to use narrow-pore catalysts. Onthe other hand, when processing feedstocks of high metals content, themetals tend to deposit rapidly on the catalyst surface and plug thepores of conventional hydrogen processing catalysts, resulting in a lossof catalytic activity for sulfur and nitrogen removal. In order tomaintain hydrotreating activity, it is necessary that the catalyst behigh in surface area. To facilitate the diffusion of large componentsinto and out of the catalyst and to prevent surface deposits of coke andmetals, large pore diameters are required. These criteria necessitatethe use of bimodal catalysts which have high surface areas and asignificant fraction of pore volume in large pores. The large poresallow enhanced diffusion of large molecules into the catalyst while thesmaller pores, providing most of the surface area, allow forhydroprocessing of the feed. Catalysts of this type can be used ashydrotreating catalysts, especially for residue/demetallizationapplications.

SUMMARY OF THE INVENTION

The present invention relates to a process for the preparation ofbimodal catalysts having surface areas at least about 300 m² /g with asignificant fraction (at least about 20%) of the pore volume located inpores having diameters greater than about 350 Å and a significantfraction of pores (at least about 20%) in diameters less than about 70Å. These catalysts are prepared by a process which comprises:

(a) titrating an aqueous solution of an acid aluminum salt and anaqueous solution of a basic aluminum compound in the presence of aphosphorus-containing compound, thereby forming a precipitate,

(b) aging the precipitate at a temperature ranging from about 20° C. toabout 90° C. for at least about 15 minutes at a pH ranging from about8.0 to about 12.0,

(c) washing the precipitate,

(d) mixing the precipitate with an element selected from the groupconsisting of nickel, cobalt, and mixtures thereof, and a heavy metalselected from the group consisting of molybdenum, tungsten, and mixturesthereof, at a pH in the range between about 4.0 and about 9.0 and atemperature in the range between about 25° C. and about 100° C. untiladsorption of the metal salts onto the gel is sufficient to yield afinal catalyst having from about 1% w to about 5% w cobalt and/or nickeland from about 8% w to about 32% w heavy metal,

(e) partially drying the product of step (d) to reduce loss on ignitionto between about 55% and about 65%,

(f) passing the product of step (e) through a mixing means,

(g) extruding the product of step (f), and

(h) drying and calcining the product of step (g) at a temperatureranging from about 300° C. to about 900° C.

It has been found that hydrogel-derived catalysts prepared according tothe invention have activities equal to or better than catalysts preparedby conventional techniques when compared on a metals efficiency basiswhile having densities significantly lower than conventionally preparedcatalysts. Two of the major advantages of the hydrogel route are highermetals utilization and lower cost of catalyst manufacture relative toconventionally prepared catalysts. The catalysts prepared according tothe invention have high surface areas, at least about 300 m² /g; atleast about 20% of the pore volume located in pores having diametersgreater than about 350 Å; and at least about 20% of the pore volumelocated in pores having diameters less than about 70 Å. These catalystsare particularly suitable for residue/demetallization applications.

The present invention also includes using catalysts prepared accordingto the invention to hydrotreat hydrocarbon feedstocks.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

In the process of the instant invention, a highly active hydrotreatingcatalyst is prepared by incorporating an element selected from the groupconsisting of nickel, cobalt and mixtures thereof, a heavy metalselected from the group consisting of molybdenum, tungsten and mixturesthereof, into a phosphated alumina hydrogel prepared by titrating anaqueous solution of an acid aluminum compound and an aqueous solution ofa basic aluminum compound in the presence of a phosphorus-containingcompound.

The phosphated alumina hydrogel can be prepared by titrating an aqueoussolution of one or more aluminum salt(s) with an appropriate acidic orbasic material or solution in the presence of a phosphorus-containingcompound to cause precipitation of the phosphated alumina gel. Oneskilled in the art will recognize that the alumina gel can be preparedby titrating an acidic aluminum salt such as, for example, aluminumsulfate, aluminum nitrate, or aluminum chloride, in aqueous solutionwith a basic precipitating medium such as, for example, sodium hydroxideor ammonium hydroxide in the presence of a phosphorus-containingcompound, or, by titrating an alkali metal aluminate such as, forexample, sodium aluminate or potassium aluminate, in aqueous solutionwith an acidic precipitating medium such as, for example, hydrochloricacid or nitric acid, in the presence of a phosphorus-containingcompound. One skilled in the art will recognize that the adjustment ofthe pH of an aluminum-containing solution to between about 5.5 and about10.0 will result in precipitation of the aluminum as phosphated aluminumhydroxide or phosphated hydrated aluminum oxide.

In a preferred embodiment, the phosphated alumina hydrogel is preparedby titrating an aqueous solution of an alkali metal aluminate and anaqueous solution of an acid aluminum salt, at least one of which has aphosphorus-containing compound dissolved therein, to cause precipitationof the phosphated alumina gel. Suitable acidic aluminum salts includealuminum sulfate, aluminum nitrate and aluminum chloride. A preferredspecies is aluminum sulfate. Suitable alkali metal aluminates are sodiumaluminate and potassium aluminate. The precipitation can be carried outby adding an aqueous solution of the basic aluminum species to anaqueous solution of the acidic aluminum species or the procedure can bereversed by adding an aqueous solution of the acidic aluminum species toan aqueous solution of the basic aluminum species (referred to as"sequential precipitation"). Preferably, the precipitation in theinstant invention is carried out by simultaneously adding the acidaluminum species and the basic aluminum species, at least one of whichhas a phosphorus-containing compound dissolved therein, to causeprecipitation of the hydrogel (referred to as "simultaneousprecipitation"). The maximum rate of addition of the acid aluminumspecies and the basic aluminum species is fixed by the rate at which thetwo streams can be mixed and the pH and temperature of the system can beeffectively controlled.

As used herein, the term "a phosphorus-containing compound" is genericand refers to one phosphorus-containing compound as well as more thanone phosphorus-containing compound. The phosphorus-containing compoundis generally selected from the group consisting of phosphoric acid, aphosphate salt and mixtures thereof. Suitable phosphate salts includealkali metal phosphates, alkali metal hydrogen phosphates, ammoniumphosphate and ammonium hydrogen phosphate. The phosphorus-containingcompound is preferably phosphoric acid and is preferably mixed with theacid aluminum species prior to the precipitation. Alternatively, thephosphorus-containing compound can be sodium or ammonium phosphate andmixed with the basic aluminum species prior to precipitation. Thephosphorus-containing compound can also be added as a separate solutionor added to both the acid aluminum species and the basic aluminumspecies without significantly affecting the results. In a preferredembodiment, the phosphorus-containing compound is commercially available85% phosphoric acid although other phosphorus-containing materials maybe utilized. The amount of phosphorus-containing compound added to theacid aluminum species and/or the basic aluminum species is from about0.06 to about 0.30 moles of phosphorus per mole of aluminum.

The ranges and limitations provided in the instant specification andclaims are those which are believed to particularly point out anddistinctly claim the instant invention. It is, however, understood thatother ranges and limitations that perform substantially the samefunction in substantially the same manner to obtain the same orsubstantially the same result are intended to be within the scope of theinstant invention as defined by the instant specification and claims.

The temperature and pH of the precipitation are important variables inthe preparation of the aluminas into which metals can be incorporated toform catalysts with desirable physical qualities. One skilled in the artwould recognize that changes in precipitation temperatures and pHsresult in changes in porosities. The optimal temperatures and pHs forthe precipitation of the aluminas can be determined with a minimalamount of routine experimentation. In the instant invention, aprecipitation temperature typically ranges from about 20° C. to about90° C., preferably from about 50° C. to about 85° C., more preferablyfrom about 55° C. to about 65° C., and a precipitation pH typicallyranges between about 5.5 and about 10.0, preferably between about 5.5and about 8.0, and more preferably between about 6.0 and about 7.5. Thelength of time required for the precipitation step is typically fromabout 15 minutes to about 45 minutes. The period of time for theprecipitation should be sufficiently long for adequate mixing of thematerials, but not long enough for enhanced particle growth to occur.

After the precipitation step is completed, the pH of the slurry isadjusted to a pH in the range from about 8.0 to about 12.0, preferablyabout 8.0 to about 11.0, and more preferably from about 8.0 to about10.5, aged at a temperature in the range from about 20° C. to about 90°C., preferably about 50° C. to about 85° C. for at least 15 minutes. Anupper limit on the length of time for aging is not critical and isnormally determined by economical considerations. Aging times willtypically range from about 0.1 to about 10 hours, preferably from about0.25 to about 5 hours, and more preferably from about 0.25 to about 1hour. In general, aluminas with acceptable properties are produced byholding the aging temperature equal to the precipitation temperature.

After aging, the slurry is washed and filtered in routine fashion toremove substantially all of the removable water-soluble salts formedduring the precipitation of the phosphated hydrogel. The preferredsolvent for washing is water although other solvents such as loweralkanols may be utilized.

After washing, the metals are incorporated into the phosphated hydrogel.One method for adding the metals to the hydrogel is a reslurry step inwhich the hydrogel is reslurried with a metals solution containingsolubilized salts of an element selected from the group consisting ofnickel, cobalt and mixtures thereof, and a heavy metal selected from thegroup consisting of molybdenum, tungsten and mixtures thereof,sufficient to deposit on the final catalyst from about 1% w to about 5%w nickel and/or cobalt and from about 8% w to about 18% w molybdenum orabout 10% w to about 32% w tungsten. When mixtures of molybdenum andtungsten are utilized, the final catalyst contains from about 8% w toabout 32% w molybdenum and tungsten. The solution may, however, containamounts of nickel and/or cobalt and molybdenum or tungsten in excess ofthat required to deposit the aforesaid amounts of metals, which excessmay be removed by washing or other techniques following the reslurrystep. A typical metals solution can be prepared by combining amolybdenum and/or tungsten solution with a nickel and/or cobaltsolution. In a preferred embodiment, the metals solution contains astabilizing amount of a phosphorus-containing compound. Typically, themetals solution contains a phosphorus-containing compound in an amountof from about 0.2 to about 1.5 moles of phosphorus per mole ofmolybdenum or tungsten. Suitable phosphorus-containing compounds are theacids of phosphorus and their salts. Typical acids of phosphorus includephosphoric acids, phosphonic acids, phosphinic acids, phosphorous acidsand the like. The phosphorus-containing compound is generally selectedfrom the group consisting of phosphoric acid, a phosphate salt andmixtures thereof. Suitable phosphate salts include alkali metalphosphates, alkali metal hydrogen phosphates, ammonium phosphate andammonium hydrogen phosphate.

The molybdenum solution consists of a water-soluble source of molybdenumoxide such as ammonium heptamolybdate or ammonium dimolybdate dissolvedin water and optionally, a phosphorus-containing compound. Hydrogenperoxide may also be used to aid in solution preparation in some cases.A preferred method for preparing the molybdenum solution consists ofadding hydrogen peroxide to the solution in the range of about 0.1 toabout 1.0 mole of hydrogen peroxide per mole of molybdenum. Optionally,a suitable soluble amine compound such as monoethanolamine,propanolamine or ethylenediamine may be added to the molybdenum solutionin order to aid in stabilization of the solution.

The tungsten solution typically consists of ammonium metatungstatedissolved in water and optionally, a phosphorus-containing compound. Apreferred method for preparing the tungsten solution consists of addinghydrogen peroxide to the solution in the range of about 0.1 to about 1.0mole of hydrogen peroxide per mole of tungsten. In addition, a suitablesoluble amine compound such as monoethanolamine, propanolamine orethylenediamine may be added to the tungsten solution in order to aid instabilization of the solution.

The nickel solution consists of nickel salts dissolved in water andoptionally, a phosphorus-containing compound. A wide range of nickelcompounds are suitable, such as nickel nitrate, nickel acetate, nickelformate, nickel sulfate, nickel oxide, nickel phosphate, nickelcarbonate, nickel chloride, and nickel hydroxide. Two compounds that areespecially useful are nickel nitrate and nickel carbonate.

The cobalt solution consists of cobalt salts dissolved in water andoptionally, a phosphorus-containing compound. A wide range of cobaltcompounds are suitable, such as cobalt nitrate, cobalt hydroxide, cobaltacetate, cobalt oxalate, or cobalt oxide. The preferred cobalt compoundis cobalt nitrate.

An alternative method for incorporating the metals into the phosphatedhydrogel is to add dry, water-soluble metal salts of an element selectedfrom the group consisting of nickel, cobalt and mixtures thereof, anddry, water-soluble salts of a heavy metal selected from the groupconsisting of molybdenum, tungsten and mixtures thereof, to thephosphated hydrogel and mix until dissolution and adsorption of themetal salts and phosphorus onto the gel is substantially complete. Themetal salts of nickel and/or cobalt and molybdenum and/or tungsten areadded to the hydrogel in amounts sufficient to incorporate into thefinal catalyst from about 1% w to about 5% w cobalt and from about 8% wto about 18% w molybdenum or about 10% w to about 32% w tungsten. Whenmixtures of molybdenum and tungsten are utilized, the final catalystcontains about 8% w to about 32% w molybdenum and tungsten.

Molybdenum is generally added to the hydrogel as a dry, watersolublesource of molybdenum such as ammonium heptamolybdate or ammoniumdimolybdate. Tungsten is typically added to the hydrogel as ammoniummetatungstate. Nickel is preferably added to the hydrogel in the form ofdry, water-soluble nickel nitrate, nickel acetate, nickel formate,nickel sulfate, nickel oxide, nickel phosphate, nickel carbonate, nickelchloride or nickel hydroxide, with nickel nitrate and nickel carbonatebeing preferred. Cobalt is added to the hydrogel in the form of dry,watersoluble cobalt nitrate, cobalt hydroxide, cobalt acetate, cobaltoxalate or cobalt oxide, with cobalt nitrate being preferred. In apreferred embodiment, a phosphorus-containing compound is added alongwith the metal salts to the phosphated hydrogel. Thephosphorus-containing compound is typically added, either wet or dry, tothe hydrogel in an amount ranging from about 0.2 to about 1.5 moles ofphosphorus per mole of molybdenum or tungsten. The phosphorus-containingcompound is preferably added directly to the hydrogel as phosphoricacid, a phosphate salt or mixtures thereof. Suitable phosphate saltsinclude alkali metal phosphates, alkali metal hydrogen phosphates,ammonium phosphate and ammonium hydrogen phosphate. Alternatively, thephosphorus-containing compound and the dry nickel and/or cobalt salt canbe mixed prior to addition to the phosphated hydrogel.

A preferred method of mixing the dry metal salts of nickel and/or cobaltand molybdenum and/or tungsten with the phosphated hydrogel consists ofadding hydrogen peroxide to the mixture of dry metal salts and hydrogelin an amount ranging from about 0.1 to about 1.0 mole of hydrogenperoxide per mole of molybdenum and/or tungsten. Optionally, a suitableamine compound such a monoethanolamine, propanolamine or ethylenediaminemay be added to the mixture of dry metal salts and hydrogel in order toaid in stabilization of the mixture of the metal salts and thephosphated hydrogel.

The dry metal salts of nickel and/or cobalt, molybdenum and/or tungstenand optionally, the phosphorus-containing compound (if added dry) aretypically added to the hydrogel in the form of finely divided particleswhich are generally 100 mesh or less in size. While particle size is notcritical and larger particle sizes may be utilized, it is economicallyadvantageous to use particles which are 100 mesh or less in size.

It is also within the scope of this invention to combine the two methodsdescribed above for adding the metals to the phosphated hydrogel. Forexample, one metal may be added to the hydrogel as a dry salt andanother added in the form of a solution. Various permutations of thiscombination of dry salts additions and metals solutions additions wouldbe obvious to one skilled in the art.

The temperature and pH of the step in which the metals solutions and/orthe dry metal salts are mixed with the phosphated hydrogel are importantvariables in the preparation of hydrogel-derived catalysts which haveacceptable densities and porosities. The temperature of the reslurryand/or mixing step affects the catalysts only when aphosphorus-containing compound is added to the hydrogel along with themetals, with the trend being for higher temperatures to yield lowerdensity catalysts. The mixing of the phosphated hydrogel with the metalssolution or the dry metal salts is carried out at a pH in the rangebetween about 4.0 and about 10.0, preferably between about 4.0 and about9.0, more preferably between about 4.0 and about 8.0, and a temperaturein the range between about 25° C. and about 100° C., preferably betweenabout 25° C. and about 80° C., until incorporation of the metals saltsinto the gel is sufficient to yield a final calcined catalyst havingfrom about 1% w to about 5% w nickel and/or cobalt and from 8% w toabout 32% w heavy metal selected from the group consisting ofmolybdenum, tungsten and mixtures thereof. Typically, the times formixing the hydrogel and the metals will range from about 0.5 to about 2hours. Optionally, the resulting material can be washed to removeunadsorbed metals and filtered in routine fashion.

Following the addition of the metals to the phosphated hydrogel, theresulting material is partially dried to reduce loss on ignition (LOI)from about 90% to between about 55% and about 65%, preferably betweenabout 55% and about 60%. As used herein, "loss on ignition" is equal tothe amount of volatiles present in the hydrogel divided by the amount ofvolatiles present in the hydrogel plus the dry weight of the hydrogelmultiplied by 100 percent. This reduction in the volatiles content ofthe hydrogel is critical to the formation of catalysts having at leastabout 20% of the pore volume in pores having diameters greater thanabout 350 Å and at least about 20% of the pore volume in pores havingdiameters less than about 70 Å. Materials which are not dried to theindicated LOIs do not produce the desired bimodal pore sizedistribution. In addition, materials which are too wet result incatalysts having poor physical properties and materials which are toodry cannot be extruded in a conventional manner. The partially driedmaterial is then passed through a mixing means to peptize the gel andthus form linkages in order for the materials to be acceptable forconventional extrusion. Suitable mixing means include a work-intensivemixer such as, for example, a Readco Continuous Processor, or any otherhigh shear, intensive work apparatus which peptizes the gel and rendersthe partially dried materials acceptable for conventional extrusion. Thepartially dried material is then extruded using conventional methodssuch as, for example, a Bonnot extruder, dried more completely andcalcined. Drying is accomplished by conventional means. It may becarried out by forced draft drying, vacuum drying, air drying or similarmeans. Drying temperatures are not critical and depend upon theparticular means utilized for drying. Drying temperatures will typicallyrange from about 50° C. to about 150° C.

After drying, the material is calcined to produce the finished catalyst.The material may be calcined in an oxidizing or neutral atmosphere,although air is preferred. However, if binders and/or lubricants areused the material is heated in an oxygen-containing atmosphere,preferably air, in order to burn out the binders and lubricants.Calcining temperatures will typically range from about 300° C. to about900° C. Burn-out temperatures will depend on the concentration of oxygenin the burn-out atmosphere as well as the burn-out time involved.Typically, burn-out temperatures will range from about 300° C. to about900° C. Drying, calcining and burn-out may be combined in one or twosteps. Most frequently the calcining and/or burn-out steps are combinedusing an oxygen-containing atmosphere.

Certain other processing steps may be incorporated into theabove-described procedure without deviating from the scope and intent ofthis invention. For example, the partially dried material can be passedthrough the extruder several times as an alternative to passing thepartially dried material through a work-intensive mixer.

The final catalysts are found to have surface areas greater than about300 m² /g, nitrogen pore volumes ranging from about 0.4 to about 1.2cc/g and with at least 20% of their mercury pore volume in pores havingdiameters greater than about 350 Å and at least about 20%, preferablyabout 35%, of their pore volume in pores having diameters less thanabout 70 Å. In general, the metals contents of the final catalysts rangefrom about 1% w to about 5% w nickel and/or cobalt, preferably fromabout 2.5% w to about 4% w nickel and/or cobalt, and from about 8% w toabout 18% w, preferably from about 10% w to about 14% w molybdenum orabout 10% w to about 32% w, preferably from about 18% w to about 26% wtungsten.

The catalysts prepared in the instant invention can be suitably appliedto hydrocarbon conversion processes such as hydrocracking,hydrotreating, isomerization, hydrogenation, dehydrogenation,oligomerization, alkylation, dealkylation and the like.

The catalysts of the instant invention are most commonly employed inhydrotreating and/or hydrocracking feedstocks ranging in volatilitiesfrom naphthas to petroleum residues, including materials derived fromtar sands, shale oils and the like. Reaction temperatures will typicallyrange from about 300° F. to about 900° F., preferably from about 500° F.to about 850° F. Reaction pressures are generally within the range ofabout 200 psig to about 3500 psig, preferably from about 600 psig toabout 2500 psig. Reactions are conducted at liquid hourly spacevelocities within the range of about 0.05 to about 15 reciprocal hour.

Multiple uses of these feedstocks after treating with the catalysts ofthis invention are possible. Depending on the particular feedstockstreated, suitable uses can include conversion unit feedstocks such asthermal cracking and hydrocracking, or finished products such asgasoline, diesel, airline turbine fuel, furnace oils, solvents, fueloils and asphalts.

The process for preparing the catalysts of the instant invention will befurther described below by the following examples which are provided forillustration and which are not to be construed as limiting theinvention.

EXAMPLE 1

102.5 kilograms of aluminum sulfate/phosphoric acid solution wereprepared by solubilizing 11.2 kilograms of gibbsite (alpha-aluminatrihydrate, 34% LOI) in 88.3 kilograms of 27% sulfuric acid and adding3.0 kilograms of 85% phosphoric acid at a temperature slightly above100° C. The solution was allowed to cool to 60° C. prior to use. 75.3kilograms of sodium aluminate solution were prepared by solubilizing28.0 kilograms of gibbsite (alpha-alumina trihydrate, 34% LOI) in 47.3kilograms of 36% sodium hydroxide at a temperature slightly above 115°C. This solution was also allowed to cool to 60° C. prior to use. Thesetwo solutions were metered under computer control into a precipitationvessel containing a deionized water heel (162 kilograms) held at 60° C.,maintaining a constant pH of 7.0 and a temperature of 60° C. Theprecipitation duration was fixed at 45 minutes. After the precipitationstep was complete excess sodium aluminate solution (14.0 kilograms) wasadded to the slurry to raise the pH to the desired aging pH of 10.0.Total solution quantities used: acid - 73.5 kilograms, base - 64.0kilograms. The slurry was aged for one hour at the elevated pH. Theslurry was then filtered in a single step on a 1'×10' horizontal beltvacuum filter and washed with deionized water. The resulting phosphatedalumina hydrogel generally had a water content between 75% and 90%,basis dry weight of alumina.

Nickel nitrate hexahydrate (190.89 g) was reacted with 85% phosphoricacid (33.34 g) and diluted to 1 liter with deionized water. Ammoniumheptamolybdate (307.03 g) was reacted with 30% hydrogen peroxide (91 ml)and monoethanolamine (51.3 g) and diluted to 1 liter using deionizedwater. The two solutions were combined with intensive stirring. Aportion of phosphated alumina hydrogel (6634 g, 85.51% LOI - 961 gramsdry weight) was reslurried with this solution and allowed to react for 2hours at a pH of 5.5 (adjust with HCl) at 80° C. The slurry was thenfiltered hot and washed with 2 liters of deionized water, and thensucked dry on the Buchner funnel. The catalyst hydrogel was then driedin a forced air oven at approximately 120° C. until the LOI of the gelwas 62.5%. The material was mulled in a Simpson mix muller for 15minutes, then passed through a conventional Bonnot extruder. Drying at120 ° C. was followed by calcination at 950° F. for two hours. Theproperties of the catalyst are listed in Tables I and II.

EXAMPLE 2

A catalyst was prepared according to Example 1 except that no phosphoricacid was added to the metals solution. The properties of the catalystare listed in Tables I and II.

EXAMPLE 3

102.5 kilograms of aluminum sulfate/phosphoric acid solution wereprepared by solubilizing 11.2 kilograms of gibbsite (alpha-aluminatrihydrate, 34% LOI in 88.3 kilograms of 27% sulfuric acid and adding3.0 kilograms of 85% phosphoric acid at a temperature slightly above100° C. The solution was allowed to cool to 60° C. prior to use. 75.3kilograms of sodium aluminate solution were prepared by solubilizing28.0 kilograms of gibbsite (alpha-alumina trihydrate, 34% LOI) in 47.3kilograms of 36% sodium hydroxide at a temperature slightly above 115°C. This solution was also allowed to cool to 60° C. prior to use. Thesetwo solutions were metered under computer control into a precipitationvessel containing a deionized water heel (162 kilograms) held at 60° C.,maintaining a constant pH of 7.0 and a temperature of 60° C. Theprecipitation duration was fixed at 45 minutes. After the precipitationstep was complete excess sodium aluminate solution (14.0 kilograms) wasadded to the slurry to raise the pH to the desired aging pH of 10.0.Total solution quantities used: acid - 77.5 kilograms, base - 64.9kilograms. The slurry was aged for one hour at the elevated pH. Theslurry was then filtered in a single step on a 1'×10' horizontal beltvacuum filter and washed with deionized water. The resulting phosphatedalumina hydrogel generally had a water content between 75% and 90%,basis dry weight of alumina.

Cobalt nitrate hexahydrate (163.24 g) was reacted with 85% phosphoricacid (25.53 g) and diluted to 1 liter with deionized water. Ammoniumheptamolybdate (329.47 g) was reacted with 30% hydrogen peroxide (97 ml)and monoethanolamine (55.1 g) and diluted to 1 liter using deionizedwater. The two solutions were combined with intensive stirring. Aportion of phosphated alumina hydrogel (6634 g, 85.51% LOI - 961 gramsdry weight) was reslurried with this solution and allowed to react for 2hours at a pH of 5.0 (adjust with HCl) at 25° C. The slurry was thenfiltered and washed with 2 liters of deionized water, and then suckeddry on the Buchner funnel. The catalyst hydrogel was then dried in aforced air oven at approximately 120° C. until the LOI of the gel was62.5%. The material was mulled in a Simpson mix muller for 15 minutes,then passed through the Readco mixer. The material was then extrudedthrough a conventional Bonnot extruder. Drying at 120° C. was followedby calcination at 950° F. for two hours. The properties of the catalystare listed in Tables I and II.

EXAMPLE 4

A catalyst was prepared according to Example 3 except that no phosphoricacid was added to the metals solution. The properties of the catalystare listed in Tables I and II.

COMPARATIVE EXAMPLE A

A catalyst was prepared in a manner similar to Example 1 except that thematerials were not partially dried prior to extrusion. The properties ofthe catalyst are listed in Tables I and II.

COMPARATIVE EXAMPLE B

A catalyst was prepared in a manner similar to Example 3 except that thematerials were not partially dried prior to extrusion. The properties ofthe catalyst are listed in Tables I and II.

COMPARATIVE EXAMPLE C

A catalyst was prepared utilizing a non-hydrogel technique. The catalystis commercially available from Shell under the name S-317. Theproperties of the catalyst are listed in Tables I and II.

CATALYST TESTING

Catalyst samples were used to hydrotreat a catalytically-cracked heavygas oil (CCHGO) in a trickle-flow reactor. Ten ccs of the extrudedcatalyst were crushed and sieved to a 16-45 mesh, diluted with siliconcarbide, and loaded into a typical trickle-flow reactor tube. Thecatalyst was presulfided with a 5% H₂ S/H₂ (v/v) gas mixture at 700° F.for 2 hours prior to testing. A CCHGO was passed over the catalyst at675° F. and 850 psig H₂ with a H₂ /oil equal to 4.0. Rate constants arereported relative to the non-hydrogel catalyst (Comparative Example C)and are calculated basis the total metals content of the catalyst.Measured rate constants include hydrogenation, denitrification anddesulfurization. Specific catalyst performance characteristics arepresented in Table III.

                                      TABLE I    __________________________________________________________________________    Catalyst Properties                                   COMPARA-                                          COMPARA-                                                 COMPARA-               EXAM-                    EXAM-                         EXAM-                              EXAM-                                   TIVE EX-                                          TIVE EX-                                                 TIVE EX-               PLE 1                    PLE 2                         PLE 3                              PLE 4                                   AMPLE A                                          AMPLE B                                                 AMPLE C    __________________________________________________________________________    Aging pH.sup.(a)               8.7  8.5  8.7  8.5  11.0-12.0                                          11.0   --    Density g/cc.sup.(b)               0.52 0.51 0.48 0.57 0.72   0.65   0.60    Reslurry pH.sup.(c)               5.0  5.0  5.0  5.0  5.0    5.5    --    N.sub.2 Surface               337.0                    330.0                         314.0                              320.0                                   428.0  447.0  240.0    Area m.sup.2 /g    N.sub.2 Pore               0.73 0.64 0.73 0.59 0.54   0.56   --    Volume cc/g.sup.(e)    LOI Prior to               62.5 62.5 62.5 62.5 ˜90                                          ˜90                                                 --    Extrusion.sup.(f)    % wt. Nickel.sup.(g)               2.6  2.8  --   --   1.2    --     2.52    % wt. Cobalt.sup.(g)               --   --   2.1  2.4  --     2.3    --    % wt. Molybdenum.sup.(h)               11.0 12.0 12.0 12.0 11.8   11.8   12.0    % wt. Phosphorus.sup.(i)               3.4  2.2  3.0  2.4  3.4    3.7    0.0    __________________________________________________________________________

                                      TABLE II    __________________________________________________________________________    Catalyst Pore Size Distributions                                         COM-      COM-    COM-    Hg Pore.sup.(j)                      PARATIVE  PARATIVE                                                           PARATIVE    Size Dist           EXAMPLE 1                  EXAMPLE 2                         EXAMPLE 3                                  EXAMPLE 4                                         EXAMPLE A EXAMPLE B                                                           EXAMPLE    __________________________________________________________________________                                                           C    <50 ang           25.3   23.0   15.9     29.1   86.3      91.3     2.6    50-70 ang           26.9   28.5   23.8     22.3   4.8       3.4     11.6    70-100 ang           11.4   12.3   18.4     11.7   3.0       1.7     31.2    100-150 ang            6.1    6.0    8.3      7.1   2.8       0.5     24.4    150-350 ang           11.4    5.9    8.8      7.7   2.5       0.0     11.0    >350 ang           18.9   27.3   24.7     22.0   0.7       3.2     19.3    __________________________________________________________________________     .sup.(a) Measured using an Orion 231 pH meter and Orion electrodes.     .sup.(b) 209 cc volume fully settled in a graduated cup and weighed.     .sup.(c) Measured using an Orion 231 pH meter and Orion electrodes.     .sup.(d) BET (Brunaeur, S., Emmet, P. Y. and Teller, E., J. Am. Chem.     Soc., 60, 309-316 (1938)) by nitrogen adsorption/desorption, Micromeritic     Digisorb 2500 Instrument.     .sup. (e) By nitrogen adsorption, Micromeritics Digisorb 2500 Instrument.     .sup.(f) Losson-ignition: the fraction of volatile materials removed when     held at 950° F. for two hours, expressed as a percentage of the     original weight.     .sup.(g) Weight percent determined by neutron activation analysis or     atomic absorption spectroscopy.     .sup.(h) Weight percent determined by neutron activation analysis or     atomic absorption spectroscopy.     .sup.(i) Weight percent determined by neutron activation analysis or     atomic absorption spectroscopy.     .sup.(j) Determined by mercury intrusion, to 60,000 psi using a     Micromeritics Autopore 9210, using a 130° contact angle and 0.473     N/m surface tension of mercury. Numbers listed are percent pore volume.

                                      TABLE III    __________________________________________________________________________    Specific Catalyst Performance                CCHGO     NO. GRAMS    WEIGHT                (METALS BASIS)                          METAL IN                                 DENSITY                                       %                H  N   S  10 CC CAT.                                 G/CC  Ni                                         Co                                           Mo    __________________________________________________________________________    Example 1   1.19                   1.46                       1.28                          0.707  0.52  2.6                                         --                                           11.0    Example 3   1.12                   1.05                       1.69                          0.677  0.48  --                                         2.1                                           12.0    Example 4   0.91                   0.75                       1.15                          0.821  0.57  --                                         2.4                                           12.0    Comparative Example C                1.00                   1.00                       1.00                          0.870  0.60  2.5                                         --                                           12.0    __________________________________________________________________________

I claim as my invention:
 1. A process for preparing highly activehydrotreating catalysts having surface areas at least about 300 m² /g,at least about 20% of the pore volume in pores having diameters greaterthan about 350 Å and at least about 20% of the pore volume in poreshaving diameters less than about 70 Å, which process comprises:(a)titrating an aqueous solution of one or more aluminum salt(s) with atitrating agent in the presence of a phosphorus-containing compound,thereby forming a precipitate, (b) aging the precipitate at atemperature ranging from about 20° C. to about 90° C. for at least about15 minutes at a pH ranging from about 8.0 to about 12.0, (c) washing theprecipitate, (d) mixing the precipitate with salts of an elementselected from the group consisting of nickel, cobalt, and mixturesthereof, and salts of a heavy metal selected from the group consistingof molybdenum, tungsten, and mixtures thereof, at a pH in the rangebetween about 4.0 and about 9.0 and a temperature in the range betweenabout 24° C. and about 100° C. until adsorption of the salts onto theprecipitate is sufficient to yield a final catalyst having from about 1%w to about 5% w cobalt and/or nickel and from about 8% w to about 32% wheavy metal, (e) partially drying the product of step (d) to reduce losson ignition to between about 55% and about 65%, (f) passing the productof step (e) through a mixing means, (g) extruding the product of step(f), and (h) drying and calcining the product of step (g) at atemperature ranging from about 300° C. to about 900° C.
 2. The processof claim 1 wherein the precipitation is carried out at a pH in the rangebetween about 5.5 and about 10.0.
 3. The process of claim 1 wherein theprecipitation is carried out at a temperature between about 20° C. andabout 90° C.
 4. The process of claim 1 wherein the amount ofphosphorus-containing compound in step (a) is from about 0.06 to about0.30 moles of phosphorus per mole of aluminum.
 5. The process of claim 1wherein the aging pH is in the range between about 8.0 and about 11.0.6. The process of claim 1 wherein step (d) is carried out at a pH in therange between about 4.0 and about 8.0.
 7. The process of claim 1 whereinstep (d) contains salts of nickel and molybdenum.
 8. The process ofclaim 7 wherein, in step (d), a phosphorus-containing compound in anamount of from about 0.2 to about 1.5 moles of phosphorus per mole ofmolybdenum is added.
 9. The process of claim 7 wherein said catalystcontains from about 2.5% w to about 4% w nickel and from about 8% w toabout 18% w molybdenum.
 10. The process of claim 1 wherein step (d)contains solubilized salts of cobalt and molybdenum.
 11. The process ofclaim 10 wherein, in step (d), a phosphorus-containing compound in anamount of from about 0.2 to about 1.5 moles of phosphorus per mole ofmolybdenum is added.
 12. The process of claim 10 wherein said catalystcontains from about 2.5% w to aout 4% w cobalt and from about 8% w toabout 18% w molybdenum.
 13. The process of claim 1 wherein, in step (d),a phosphorus-containing compound in an amount of from about 0.2 to about1.5 moles of phosphorus per mole of heavy metal is added.
 14. A processfor preparing highly active hydrotreating catalysts having surface areasat least about 300 m² /g, at least about 20% of the pore volume in poreshaving diameters greater than about 350 Å and at least about 20% of thepore volume in pores having diameters less than about 70Å, which processcomprises:(a) precipitating an aqueous solution of one or more aluminumsalt(s) in the presence of a phosphorus-containing compound by adjustingthe pH of said solution to a range between about 5.5 and about 10.0 anda temperature in the range between about 20° C. and about 90° C.,thereby forming a precipitate, (b) aging the precipitate at atemperature ranging from about 20° C. to about 90° C. for at least about15 minutes at a pH ranging from about 8.0 to about 12.0, (c) washing theprecipitate, (d) mixing the precipitate with one or more solution(s)containing salts of a heavy metal selected from the group consisting ofmolybdenum, tungsten and mixtures thereof, and salts of an elementselected from the group consisting of nickel, cobalt and mixturesthereof, at a pH in the range between about 4.0 and about 9.0 and atemperature in the range between about 25° C. and about 100° C. untiladsorption of the salts onto the precipitate is sufficient to yield afinal catalyst having from about 1% w to about 5% w nickel and/or cobaltand from about 8% w to about 32% w heavy metal, (e) partially drying theproduct of step (d) to reduce loss on ignition to between about 55% andabout 65%, (f) passing the product of step (e) through a mixing means,(g) extruding the product of step (f), and (h) drying and calcining theproduct of step (g) at a temperature ranging from about 300° C. to about900° C.
 15. The process of claim 14 wherein the precipitation is carriedout at a pH in the range between about 5.5 and about 8.0.
 16. Theprocess of claim 14 wherein the precipitation is carried out at atemperature between about 50° C. and about 85° C.
 17. The process ofclaim 14 wherein the amount of phosphorus-containing compound in step(a) is from about 0.06 to about 0.30 moles of phosphorus per mole ofaluminum.
 18. The process of claim 14 wherein the aging pH is in therange between about 8.0 and about 11.0.
 19. The process of claim 14wherein step (d) is carried out at a pH in the range between about 4.0and about 8.0.
 20. The process of claim 14 wherein said solution step(d) contains salts of nickel and molybdenum.
 21. The process of claim 20wherein said solution in step (d) additionally contains aphosphorus-containing compound in an amount of from about 0.2 to about1.5 moles of phosphorus per mole of molybdenum.
 22. The process of claim20 wherein said catalyst contains from about 2.5% w to about 4% w nickeland from about 8% w to about 18% w molybdenum.
 23. The process of claim14 wherein said solution in step (d) contains salts of cobalt andmolybdenum.
 24. The process of claim 23 wherein said solution in step(d) additionally contains a phosphorus-containing compound in an amountof from about 0.2 to about 1.5 moles of phosphorus per mole ofmolybdenum.
 25. The process of claim 23 wherein said catalyst containsfrom about 2.5% w to about 4% w cobalt and from about 8% w to about 18%w molybdenum.
 26. The process of claim 14 wherein said solution in step(d) additionally contains a phosphorus-containing compound in an amountof from about 0.2 to about 1.5 moles of phosphorus per mole of heavymetal.
 27. A process for preparing highly active hydrotreating catalystshaving surface areas at least about 300 m² /g, at least about 20% of thepore volume in pores having diameters greater than about 350 Å and atleast about 20% of the pore volume in pores having diameters less thanabout 70 Å, which process comprises:(a) precipitating an aqueoussolution of one or more aluminum salt(s) in the presence of aphosphorus-containing compound by adjusting the pH of said solution to arange between about 5.5 and about 10.0 at a temperature in the rangebetween about 20° C. and about 90° C., thereby forming a precipitate,(b) aging the precipitate at a temperature ranging from about 20° C. toabout 90° C. for at least about 15 minutes at a pH ranging from about8.0 to about 12.0, (c) washing the precipitate, (d) mixing theprecipitate with dry, water-soluble salts of an element selected fromthe group consisting of nickel, cobalt and mixtures thereof, and dry,water soluble salts of a heavy metal selected from the group consistingof molybdenum, tungsten and mixtures thereof, at a pH in the rangebetween about 4.0 and about 9.0 and a temperature in the range betweenabout 25° C. and about 100° C. to yield a final catalyst having fromabout 1% w to about 5% w nickel and/or cobalt and from about 8% w toabout 32% w heavy metal, (e) partially drying the product of step (d) toreduce loss on ignition to between about 55% and about 65%, (f) passingthe product of step (e) through a mixing means, (g) extruding theproduct of step (f), and (h) drying and calcining the product of step(g) at a temperature ranging from about 300° C. to about 900° C.
 28. Theprocess of claim 27 wherein the precipitation is carried out at a pH inthe range between about 5.5 and about 8.0.
 29. The process of claim 27wherein the precipitation is carried out at a temperature between about50° C. and about 85° C.
 30. The process of claim 27 wherein the amountof phosphorus-containing compound in step (a) is from about 0.06 toabout 0.30 moles of phosphorus per mole of aluminum.
 31. The process ofclaim 27 wherein the aging pH is in the range between about 8.0 andabout 11.0.
 32. The process of claim 27 wherein step (d) is carried outat a pH in the range between about 4.0 and about 8.0.
 33. The process ofclaim 27 wherein said salts in step (d) are salts of nickel andmolybdenum.
 34. The process of claim 33 wherein, in step (d), aphosphorus-containing compound in an amount of from about 0.2 to about1.5 moles of phosphorus per mole of molybdenum is added.
 35. The processof claim 33 wherein said catalyst contains from about 2.5% w to about 4%w nickel and from about 8% w to about 18% w molybdenum.
 36. The processof claim 27 wherein said salts in step (d) are salts of cobalt andmolybdenum.
 37. The process of claim 36 wherein, in step (d), aphosphorous-containing compound in an amount of from about 0.2 to about1.5 moles of phosphorus per mole of molybdenum is added.
 38. The processof claim 36 wherein said catalyst contains from about 2.5% w to about 4%w cobalt and from about 8% w to about 18% w molybdenum.
 39. The processof claim 27 wherein, in step (d), a phosphorus-containing compound in anamount of from about 0.2 to about 1.5 moles of phosphorus per mole ofheavy metal is added.
 40. A process for preparing highly activehydrotreating catalysts having surface areas at least about 300 m² /g,at least about 20% of the pore volume in pores having diameters greaterthan about 350 Å and at least about 20% of the pore volume in poreshaving diameters less than about 70 Å, which process comprises:(a)precipitating an aqueous solution of one or more aluminum salt(s) in thepresence of a phosphorus-containing compound by adjusting the pH of saidsolution to a range between about 5.5 and about 10.0 at a temperature inthe range between about 20° C. and about 90° C., thereby forming aprecipitate, (b) aging the precipitate at a temperature ranging fromabout 20° C. to about 90° C. for at least about 15 minutes at a pHranging from about 8.0 to about 12.0, (c) washing the precipitate, (d)mixing a dry, water-soluble salt of a heavy metal selected from thegroup consisting of molybdenum, tungsten and mixtures thereof, and amixture of a dry, water-soluble salt selected from the group consistingof nickel, cobalt and mixtures thereof, and a phosphorus-containingcompound in an amount of from about 0.2 to about 1.5 moles of phosphorusper mole of heavy metal with the precipitate at a pH in the rangebetween about 4.0 and about 9.0 and a temperature in the range betweenabout 25° C. and about 100° C. to yield a final catalyst having fromabout 1% w to about 5% w nickel and/or cobalt and from about 8% w toabout 32% w heavy metal, (e) partially drying the product of step (d) toreduce loss on ignition to between about 55% and about 65%, (f) passingthe product of step (e) through a mixing means, (g) extruding theproduct of step (f), and (h) drying and calcining the product of step(g) at a temperature ranging from about 300° C. to about 900° C.
 41. Theprocess of claim 40 wherein the precipitation is carried out at a pH inthe range between about 5.5 and about 8.0.
 42. The process of claim 40wherein the precipitation is carried out at a temperature between about50° C. and about 85° C.
 43. The process of claim 40 wherein the amountof phosphorus-containing compound acid in step (a) is from about 0.06 toabout 0.30 moles of phosphorus per mole of aluminum.
 44. The process ofclaim 40 wherein the aging pH is in the range between about 8.0 andabout 11.0.
 45. The process of claim 40 wherein step (d) is carried outat a pH in the range between about 4.0 and about 8.0.
 46. The process ofclaim 40 wherein said phosphorus-containing compound in steps (a) and(d) is independently selected from the group consisting of phosphoricacid, a phosphate salt and mixtures thereof.
 47. The process of claim 40wherein said salts in step (d) salts are salts of nickel and molybdenum.48. The process of claim 47 wherein said catalyst contains from about2.5% w to about 4% w nickel and from about 8% w to about 18% wmolybdenum.
 49. The process of claim 40 wherein said salts in step (d)salts are salts of cobalt and molybdenum.
 50. The process of claim 49wherein said catalyst contains from about 2.5% w to about 4% w cobaltand from about 8% w to about 18% w molybdenum.
 51. A process forpreparing highly active hydrotreating catalysts having surface areas atleast about 300m² /g, at least about 20% of the pore volume in poreshaving diameters greater than about 350 Å and at least about 20% of thepore volume in pores having diameters less than about 70 Å, whichprocess comprises:(a) titrating an aqueous solution of an acid aluminumsalt with an aqueous solution of a basic aluminum compound in thepresence of a phosphorus-containing compound at a pH in the rangebetween about 5.5 and about 10.0 and a temperature in the range beweenabout 20° C. and about 90° C., thereby forming a precipitate, (b) agingthe precipitate at a temperature ranging from about 20° C. to about 90°C. for at least about 15 minutes at a pH ranging from about 8.0 to about12.0, (c) washing the precipitate, (d) mixing the precipitate with oneor more solution(s) containing salts of a heavy metal selected from thegroup consisting of molybdenum, tungsten and mixtures thereof, and saltsof an element selected from the group consisting of nickel, cobalt andmixtures thereof, at a pH in the range between about 4.0 and about 9.0and a temperature in the range between about 25° C. and about 100° C.until adsorption of the salts onto the precipitate is sufficient toyield a final catalyst having from about 1% w to about 5% w nickeland/or cobalt and from about 8% w to about 32% w heavy metal, (e)partially drying the product of step (d) to reduce loss on ignition tobetween about 55% and about 65%, (f) passing the product of step (e)through a mixing means, (g) extruding the product of step (f), and (h)drying and calcining the product of step (g) at a temperature rangingfrom about 300° C. to about 900° C.
 52. The process of claim 51 whereinthe precipitation is carried out at a pH in the range between about 5.5and about 8.0.
 53. The process of claim 51 wherein the precipitation iscarried out at a temperature between about 50° C. and about 85° C. 54.The process of claim 51 wherein the amount of phosphorus-containingcompound in step (a) is from about 0.06 to about 0.30 moles ofphosphorus per mole of aluminum.
 55. The process of claim 51 wherein theaging pH is in the range between about 8.0 and about 11.0.
 56. Theprocess of claim 51 wherein step (d) is carried out at a pH in the rangebetween about 4.0 and about 8.0.
 57. The process of claim 51 whereinsaid solution in step (d) contains salts of nickel and molybdenum. 58.The process of claim 57 wherein said solution in step (d) additionallycontains a phosphorus-containing compound in an amount of from about 0.2to about 1.5 moles of phosphorus per mole of molybdenum.
 59. The processof claim 57 wherein said catalyst contains from about 2.5% w to about 4%w nickel and from about 8% w to about 18% w molybdenum.
 60. The processof claim 51 wherein said solution in step (d) contains salts of cobaltand molybdenum.
 61. The process of claim 60 wherein said solution instep (d) additionally containins a phosphorus-containining compound inan amount of from about 0.2 to about 1.5 moles of phosphorus per mole ofmolybdenum.
 62. The process of claim 60 wherein said catalyst containsfrom about 2.5% w to about 4% w cobalt and from about 8% w to about 18%w molybdenum.
 63. The process of claim 51 wherein said solution in step(d) additionally contains a phosphorus-containing compound in an amountof from about 0.2 to about 1.5 moles of phosphorus per mole of heavymetal.
 64. A process for preparing highly active hydrotreating catalystshaving surface areas at least about 300 m² /g, at least about 20% of thepore volume in pores having diameters greater than about 350 Å and atleast about 20% of the pore volume in pores having diameters less thanabout 70 Å, which process comprises:(a) titrating an aqueous solution ofan acid aluminum salt with an aqueous solution of a basic aluminumcompound in the presence of a phosphorus-containing compound at a pH inthe range between about 5.5 and about 10.0 and a temperature in therange between about 20° C. and about 90° C., thereby forming aprecipitate, (b) aging the precipitate at a temperature ranging fromabout 20° C. to about 90° C. for at least about 15 minutes at a pHranging from about 8.0 to about 12.0, (c) washing the precipitate, (d)mixing the precipitate with dry, water-soluble salts an element selectedfrom the group consisting of nickel, cobalt and mixtures thereof, anddry, water-soluble salts of a heavy metal selected from the groupconsisting of molybdenum, tungsten and mixtures thereof, at a pH in therange between about 4.0 and about 9.0 and a temperature in the rangebetween about 25° C. and about 100° C. to yield a final catalyst havingfrom about 1% w to about 5% w nickel and/or cobalt and from about 8% wto about 32% w heavy metal, (e) partially drying the product of step (d)to reduce loss on ignition to between about 55% and about 65%, (f)passing the product of step (e) through a mixing means, (g) extrudingthe product of step (f), and (h) drying and calcining the product ofstep (g) at a temperature ranging from about 300° C. to about 900° C.65. The process of claim 64 wherein the precipitation is carried out ata pH in the range between about 5.5 and about 8.0.
 66. The process ofclaim 64 wherein the precipitation is carried out at a temperaturebetween about 50° C. and about 85° C.
 67. The process of claim 64wherein the amount of phosphorus-containing compound in step (a) is fromabout 0.06 to about 0.30 moles of phosphorus per mole of aluminum. 68.The process of claim 64 wherein the aging pH is in the range betweenabout 8.0 and about 11.0.
 69. The process of claim 64 wherein step (d)is carried out at a pH in the range between about 4.0 and about 8.0. 70.The process of claim 64 wherein said salts in step (d) are salts ofnickel and molybdenum.
 71. The process of claim 70 wherein, in step (d),a phosphorus-containing compound in an amount of from about 0.2 to about1.5 moles of phosphorus per mole of molybdenum is added.
 72. The processof claim 70 wherein said catalyst contains from about 2.5% w to about 4%w nickel and from about 8% w to about 18% w molybdenum.
 73. The processof claim 64 wherein said salts in step (d) are salts of cobalt andmolybdenum.
 74. The process of claim 73 wherein, in step (d), aphosphorus-containing compound in an amount of from about 0.2 to about1.5 moles of phosphorus per mole of molybdenum is added.
 75. The processof claim 73 wherein said catalyst contains from about 2.5% w to about 4%w cobalt and from about 8% w to about 18% w molybdenum.
 76. The processof claim 64 wherein, in step (d), a phosphorus-containing compound in anamount of from about 0.2 to about 1.5 moles of phosphorus per mole ofheavy metal is added.
 77. A process for preparing highly activehydrotreating catalysts having surface areas at least about 300 m² /g,at least about 20% of the pore volume in pores having diameters greaterthan about 350 Å and at least about 20% of the pore volume in poreshaving diameters less than about 70 Å, which process comprises:(a)titrating an aqueous solution of an acid aluminum salt with an aqueoussolution of a basic aluminum compound in the presence of aphosphorus-containing compound at a pH in the range between about 5.5and about 10.0 and a temperature in the range between about 20° C. andabout 90° C., thereby forming a precipitate, (b) aging the precipitateat a temperature ranging from about 20° C. to about 90° C. for at leastabout 15 minutes at a pH ranging from about 8.0 to about 12.0, (c)washing the precipitate, (d) mixing a dry, water-soluble salt of heavymetal selected from the group consisting of molybdenum, tungsten andmixtures thereof, and a mixture of a dry, water-soluble salt selectedfrom the group consisting of nickel, cobalt and mixtures thereof, and aphosphorus-containing compound in an amount of from about 0.2 to about1.5 moles of phosphorus per mole of heavy metal with the precipitate ata pH in the range between about 4.0 and about 9.0 and a temperature inthe range between about 25° C. and about 100° C. to yield a finalcatalyst having from about 1% w to about 5% w nickel and/or cobalt andfrom about 8% w to about 32% w heavy metal, (e) partially drying theproduct of step (d) to reduce loss on ignition to between about 55% andabout 65%, (f) passing the product of step (e) through a mixing means,(g) extruding the product of step (f), and (h) drying and calcining theproduct of step (g) at a temperature ranging from about 300° C. to about900° C.
 78. The process of claim 77 wherein the precipitation is carriedout at a pH in the range between about 5.5 and about 8.0.
 79. Theprocess of claim 77 wherein the precipitation is carried out at atemperature between about 50° C. and about 85° C.
 80. The process ofclaim 77 wherein the amount of phosphorus-containing compound in step(a) is from about 0.06 to about 0.30 moles of phosphorus per mole ofaluminum.
 81. The process of claim 77 wherein the aging pH is in therange between about 8.0 and about 11.0.
 82. The process of claim 77wherein step (d) is carried out at a pH in the range between about 4.0and about 8.0.
 83. The process of claim 77 wherein saidphosphorus-containing compound in steps (a) and (d) is independentlyselected from the group consisting of phosphoric acid, a phosphate saltand mixtures thereof.
 84. The process of claim 77 wherein said salts instep (d) are salts of nickel and molybdenum.
 85. The process of claim 84wherein said catalyst contains from about 2.5% w to about 4% w nickeland from about 8% w to about 18% w molybdenum.
 86. The process of claim77 wherein said salts in step (d) are salts of cobalt and molybdenum.87. The process of claim 86 wherein said catalyst contains from about2.5% w to about 4% w cobalt and from about 8% w to about 18% wmolybdenum.
 88. A process for preparing highly active hydrotreatingcatalysts having surface areas at least about 300 m² /g, at least about20% of the pore volume in pores having diameters greater than about 350° and at least about 20% of the pore volume in pores having diametersless than about 70Å, which process comprises:(a) titrating an aqueoussolution of an acid aluminum salt selected from the group consisting ofaluminum sulfate, aluminum nitrate and aluminum compound selected fromthe group consisting of sodium aluminate and potassium aluminate, in thepresence of a phosphorus-containing compound at a pH in the rangebetween about 5.5 and about 8.0 and a temperature in the range betweenabout 20° C. and about 90° C., thereby forming a precipitate, (b) agingthe precipitate at a temperature ranging from about 20° C. to about 90°C. for at least about 5.5 minutes at a pH ranging from about 8.0 toabout 11.9, (c) washing the precipitate, (d) mixing the precipitate withone or more solution(s) containing molybdate or dimolybdate salts andnickel salts, and phosphoric acid in an amount of from about 0.2 toabout 1.5 moles of phosphorus per mole of molybdenum at a pH in therange between about 4.0 and about 8.0 and a emperature in the rangebetween about 25° C. and about 100° C. until adsorption of the saltsonto the precipitate is sufficient to yield a final catalyst having fromabout 2.5% w to about 4% w nickel and from about 10% w to about 14% wmolybdenum, (e) partially drying the product of step (d) to reduce losson ignition to between about 55% and about 65%, (f) passing the productof step (e) through a mixing means, (g) extruding the product of step(f), and (h) drying and calcining the product of step (g) at atemperature ranging from about 300° C. to about 900° C.
 89. A processfor preparing highly active hydrotreating catalysts having surface areasat least about 300 m² /g, at least about 20% of the pore volume in poreshaving diameters greater than about 350° and at least about 20% of thepore volume in pores having diameters less than about 70Å, which processcomprises:(a) titrating an aqueous solution of an acid aluminum saltselected from the group consisting of aluminum sulfate, aluminum nitrateand aluminum chloride, with an aqueous solution of a basic aluminumcompound selected from the group consisting of sodium aluminate andpotassium aluminate, in the presence of a phosphorus-containing compoundat a pH in the range between about 5.5 and about 8.0 and a temperaturein the range between about 20° C. and about 90° C., thereby forming aprecipitate, (b) aging the precipitate at a temperature ranging fromabout 20° C. to about 90° C. for at least about 15 minutes at a pHranging from about 8.0 to about 11.0, (c) washing the precipitate, (d)mixing the precipitae with one or more solution(s) containing molybdateor dimolybdate salts and cobalt salts and phosphoric acid in an amountof from about 0.2 to about 1.5 moles of phosphorus per mole ofmolybdenum at a pH in the range between about 4.0 and about 8.0 and atemperature in the range between about 25° C. and about 100° C. untiladsorption of the salts onto the precipitate is sufficient to yield afinal catalyst having from about 2.5% w to about 4% w cobalt and fromabout 10% w to about 14% w molybdenum, (e) partially drying the productof step (d) to reduce loss on ignition to between about 55% and about65%, (f) passing the product of step (e) through a mixing means, (g)extruding the product of step (f), and (h) drying the calcining theproduct of step (g) at temperature ranging from about 300° C. to about900° C.
 90. A process for preparing highly active hydrotreatingcatalysts having surface areas at least about 300 m² /g, at least about20% of the pore volume in pores having diameters greater than about 350°and at lest about 20% of the pore volume in pores having diameters lessthan about 70 Å, which process comprises:(a) titrating an aqueoussolution of an acid aluminum salt selected from the group consisting ofaluminum sulfate, aluminum nitrate and aluminum chloride, with anaqueous solution of a basic aluminum compound selected from the groupconsisting of sodium aluminate and potassium aluminate, in the presenceof a phosphorus-containing compound at a pH in the range between about5.5 and about 8.0 and a temperature in the range between about 20° C.and about 90° C., thereby forming a precipitate, (b) aging theprecipitate at a temperature ranging from about 20° C. to about 90° C.for at least about 15 minutes at a pH ranging from about 8.0 to about11.0, (c) washing the precipitate, (d) mixing the precipitate with oneor more solution(s) containing molybdate or dimolybdate salts and cobaltsalts and phosphoric acid in an amount of from about 0.2 to about 2.5moles of phosphorus per mole of molybdenum at a pH in the range betweenabout 4.0 and about 8.0 and a temperature in the range between about 25°C. and about 100° C. until adsoprtion of the salts onto the precipitateis sufficient to yield a final catalyst having from about 2.5% w toabout 4% w cobalt and from about 10% w to about 14% w molybdenum, (e)partially drying the product of step (d) to reduce loss on ignition tobetween about 55% and about 65%, (f) passing the product of step (e)through a mixing means, (g) extruding the product of step (f), and (h)drying and calcining the product of step (g) at a temperature rangingfrom about 300° C. to about 900° C.
 91. A process for preparing highlyactive hydrotreating catalyts having surface areas at least about 300 m²/g, at least about 20% of the pore volume in pores having diametersgreater than about 350° and at least about 20% of the pore volume inpores having diameters less than about 70 Å which process comprises:(a)titrating an aqueous solution of an acid a aluminum salt selected fromthe group consisting of aluminum sulfate, aluminum nitrate and aluminumchloride, with an aqueous solution of a basic aluminum compound selectedfrom the group consisting of sodium aluminate and potassium aluminate,in the presence of a phosphorus-containing compound at a pH in the rangebetween about 5.5 and about 8.0 and a temperature in the range betweenabout 20° C. and about 90° C., thereby forming a precipitate, (b) agingthe precipitate at a temperature ranging from about 20° C. to about 90°C. for at least about 15 minutes at a pH ranging from about 8.0 to about11.0, (c) washing the precipitate, (d) mixing the precipitate with oneor more solution(s) containing moylbdate or dimolybdate salts and cobaltsalts at a pH in the range between about 4.0 and about 8.0 and atemperature in the range between about 25° C. and about 100° C. untiladsorption of the salts onto the precipitate is sufficient to yield afinal catalyst having from about 2.5% w to about 4% w cobalt and fromabout 10% w to about 14% w molybdenum, (e) partially drying the productof step (d) to reduce loss on ignition to between about 55% and about65, (f) passing the product of step (e) through a mixing means, (g)extruding the product of step (f), and (h) drying and calcining theproduct of step (g) at a temperature ranging from about 300° C. to about900° C.
 92. A process for preparing highly active hydrotreatingcatalysts having surface areas at least about 300 m² /g, at least about20% of the pore volume in pores having diameters greater than about 350Å and at least about 20% of the pore volume in pores having diametersless than about 70 Å, which process comprises:(a) titrating an aqueoussolution of an acid aluminum salt selected from the group consisting ofaluminum sulfate, aluminum nitrate and aluminum chloride, with anaqueous solution of a basic aluminum compound selected from the groupconsisting of sodium aluminate and potassium aluminate, in the presenceof a phosphorus-containing compound at a pH in the range between about5.5 and about 8.0 at a temperature in the range between about 20° C. andabout 90° C., thereby forming a precipitate, (b) aging the precipitateat a temperature ranging from about 20° C to about 90° C. for at leastabout 15 minutes at a pH ranging from about 8.0 to about 11.0,(c)washing the precipitate, (d) mixing the precipitate with dry,water-soluble nickel salts, dry, water-soluble molybdate or dimolybdatesalts, and phosphoric acid in an amount of from about 0.2 to about 1.5moles of phosphorus per mole of molybdenum, at a pH in the range betweenabout 4.0 and about 8.0 and a temperature in the range between about 25°C. and about 100° C. to yield a final catalyst having from about 2.5% wto about 4% w nickel and from about 10% w to about 14% w molybdenum, (e)partially drying the product of step (d) to reduce loss on ignition tobetween about 55% and about 65%, (f) passing the product of step (e)through a mixing means, (g) extruding the product of step (f), and (h)drying and calcining the product of step (g) at a temperature rangingfrom about 300° C. to about 900° C.
 93. A process for preparing highlyactive hydrotreating catalysts having surface areas at least about 300m² /g, at least about 20% of the pore volume in pores having diametersgreater than about 350 Å and at least about 20% of the pore volume inpores having diameters less than about 70 Å, which process comprises:(a)titrating an aqueous solution of an acid aluminum salt selected from thegroup consisting of aluminum sulfate, aluminum nitrate and aluminumchloride, with an aqueous solution of a basic aluminum compound selectedfrom the group consisting of sodium aluminate and potassium aluminate,in the presence of a phosphorus-containing compound at a pH in the rangebetween about 5.5 and about 8.0 at a temperature in the range betweenabout 20° C. and about 90° C., thereby forming a precipitate, (b) agingthe precipitate at a temperature ranging from about 20° C to about 90°C. for at least about 15 minutes at a pH ranging from about 8.0 to about11.0, (c) washing the precipitate, (d) mixing the precipitate with dry,water-soluble nickel salts and dry, water-soluble molybdate ordimolybdate salts at a pH in the range between about 4.0 and about 8.0and a temperature in the range between about 25° C. and about 100° C. toyield a final catalyst having from about 2.5% w to about 4% w nickel andfrom about 10% w to about 14% w molybdenum, (e) partially drying theproduct of step (d) to reduce loss on ignition to between about 55% andabout 65%, (f) passing the product of step (e) through a mixing means,(g) extruding the product of step (f), and (h) drying and calcining theproduct of step (g) at a temperature ranging from about 300° C. to about900° C.
 94. A process for preparing highly active hydrotreatingcatalysts having surface areas at least about 300 m² /g, at least about20% of the pore volume in pores having diameters greater than about 350Å and at least about 20% of the pore volume in pores having diametersless than about 70 Å, which process comprises:(a) titrating an aqueoussolution of an acid aluminum salt selected from the group consisting ofaluminum sulfate, aluminum nitrate and aluminum chloride, with anaqueous solution of a basic aluminum compound selected from the groupconsisting of sodium aluminate and potassium aluminate, in the presenceof a phosphorus-containing compound at a pH in the range between about5.5 and about 8.0 at a temperature in the range between about 20° C. andabout 90° C., thereby forming a precipitate, (b) aging the precipitateat a temperature ranging from about 20° C to about 90° C. for at leastabout 15 minutes at a pH ranging from about 8.0 to about 11.0, (c)washing the precipitate, (d) mixing the precipitate with dry,water-soluble cobalt salts, dry, water-soluble molybdate or dimolybdatesalts, and phosphoric acid in an amount of from about 0.2 to about 1.5moles of phosphorus per mole of molybdenum, at a pH in the range betweenabout 4.0 and about 8.0 and a temperature in the range between about 25°C. and about 100° C. to yield a final catalyst having from about 2.5% wto about 4% w cobalt and from about 10% w to about 14% w molybdenum, (e)partially drying the product of step (d) to reduce loss on ignition tobetween about 55% and about 65%, (f) passing the product of step (e)through a mixing means, (g) extruding the product of step (f), and (h)drying and calcining the product of step (g) at a temperature rangingfrom about 300° C. to about 900° C.
 95. A process for preparing highlyactive hydrotreating catalysts having surface areas at least about 300m² /g, at least about 20% of the pore volume in pores having diametersgreater than about 350 Å and at least about 20% of the pore volume inpores having diameters less than about 70 Å, which process comprises:(a)titrating an aqueous solution of an acid aluminum salt selected from thegroup consisting of aluminum sulfate, aluminum nitrate and aluminumchloride, with an aqueous solution of a basic aluminum compound selectedfrom the group consisting of sodium aluminate and potassium aluminate,in the presence of a phosphorus-containing compound at a pH in the rangebetween about 5.5 and about 8.0 at a temperature in the range betweenabout 20° C. and about 90° C., thereby forming a precipitate, (b) agingthe precipitate at a temperature ranging from about 20° C to about 90°C. for at least about 15 minutes at a pH ranging from about 8.0 to about11.0, (c) washing the precipitate, (d) mixing the precipitate with dry,water-soluble cobalt salts and dry, water-soluble molybdate ordimolybdate salts at a pH in the range between about 4.0 and about 8.0and a temperature in the range between about 25° C. and about 100° C. toyield a final catalyst having from about 2.5% w to about 4% w cobalt andfrom about 10% w to about 14% w molybdenum, (e) partially drying theproduct of step (d) to reduce loss on ignition to between about 55% andabout 65%, (f) passing the product of step (e) through a mixing means,(g) extruding the product of step (f), and (h) drying and calcining theproduct of step (g) at a temperature ranging from about 300° C. to about900° C.
 96. A process for preparing highly active hydrotreatingcatalysts having surface areas at least about 300 m² /g, at least about20% of the pore volume in pores having diameters greater than about 350Å and at least about 20% of the pore volume in pores having diametersless than about 70 Å, which process comprises:(a) titrating an aqueoussolution of an acid aluminum salt selected from the group consisting ofaluminum sulfate, aluminum nitrate and aluminum chloride, with anaqueous solution of a basic aluminum compound selected from the groupconsisting of sodium aluminate and potassium aluminate, in the presenceof a phosphorus-containing compound at a pH in the range between about5.5 and about 8.0 at a temperature in the range between about 20° C. andabout 90° C., thereby forming a precipitate, (b) aging the precipitateat a temperature ranging from about 20° C to about 90° C. for at leastabout 15 minutes at a pH ranging from about 8.0 to about 11.0, (c)washing the precipitate, (d) mixing a dry, water-soluble molybdate ordimolybdate salt and a mixture of a dry, water-soluble nickel salt andphosphoric acid in an amount of from about 0.2 to about 1.5 moles ofphosphorus per mole of molybdenum with the precipitate at a pH in therange between about 4.0 and about 8.0 and a temperature in the rangebetween about 25° C. and about 100° C. to yield a final catalyst havingfrom about 2.5% w to about 4% w nickel and from about 10% w to about 14%w molybdenum, (e) partially drying the product of step (d) to reduceloss on ignition to between about 55% and about 65%, (f) passing theproduct of step (e) through a mixing means, (g) extruding the product ofstep (f), and (h) drying and calcining the product of step (g) at atemperature ranging from about 300° C. to about 900° C.
 97. A processfor preparing highly active hydrotreating catalysts having surface areasat least about 300 m² /g, at least about 20% of the pore volume in poreshaving diameters greater than about 350 Å and at least about 20% of thepore volume in pores having diameters less than about 70 Å, whichprocess comprises:(a) titrating an aqueous solution of an acid aluminumsalt selected from the group consisting of aluminum sulfate, aluminumnitrate and aluminum chloride, with an aqueous solution of a basicaluminum compound selected from the group consisting of sodium aluminateand potassium aluminate, in the presence of a phosphorus-containingcompound at a pH in the range between about 5.5 and about 8.0 at atemperature in the range between about 20° C. and about 90° C., therebyforming a precipitate, (b) aging the precipitate at a temperatureranging from about 20° C to about 90° C. for at least about 15 minutesat a pH ranging from about 8.0 to about 11.0, (c) washing theprecipitate, (d) mixing a dry, water-soluble molybdate or dimolybdatesalt and a mixture of a dry, water-soluble cobalt salt and phosphoricacid in an amount of from about 0.2 to about 1.5 moles of phosphorus permole of molybdenum with the precipitate at a pH in the range betweenabout 4.0 and about 8.0 and a temperature in the range between about 25°C. and about 100° C. to yield a final catalyst having from about 2.5% wto about 4% w cobalt and from about 10% w to about 14% w molybdenum, (e)partially drying the product of step (d) to reduce loss on ignition tobetween about 55% and about 65%, (f) passing the product of step (e)through a mixing means, (g) extruding the product of step (f), and (h)drying and calcining the product of step (g) at a temperature rangingfrom about 300° C. to about 900° C.
 98. A process for preparing highlyactive hydrotreating catalysts having surface areas at least about 300m² /g, at least about 20% of the pore volume in pores having diametersgreater than about 350 Å and at least about 20% of the pore volume inpores having diameters less than about 70 Å, which process comprises:(a)titrating an aqueous solution of an acid aluminum salt selected from thegroup consisting of aluminum sulfate, aluminum nitrate and aluminumchloride, with an aqueous solution of a base in the presence of aphosphorus-containing compound at a pH in the range between about 5.5and about 8.0 and a temperature in the range between about 20° C. andabout 90° C., thereby forming a precipitate, (b) aging the precipitateat a temperature ranging from about 20° C. to about 90° C. for at leastabout 15 minutes at a pH ranging from about 8.0 to about 11.0, (c)washing the precipitate, (d) mixing the precipitate with one or moresolution(s) containing molybdate or dimolybdate salts and nickel salts,and phosphoric acid in an amount of from about 0.2 to about 1.5 moles ofphosphorus per mole of molybdenum at a pH in the range between about 4.0and about 8.0 and a temperature in the range between about 25° C. andabout 100° C. untiI adsorption of the salts onto the precipitate issufficient to yield a final catalyst having from about 2.5% w to about4% w nickel and from about 10% w to about 14% w molybdenum, (e)partially drying the product of step (d) to reduce loss on ignition tobetween about 55% and about 65%, (f) passing the product of step (e)through a mixing means, (g) extruding the product of step (f), and (h)drying and calcining the product of step (g) at a temperature rangingfrom about 300° C. to about 900° C.
 99. A process for preparing highlyactive hydrotreating catalysts having surface areas at least about 300m² /g, at least about 20% of the pore volume in pores having diametersgreater than about 350 Å and at least about 20% of the pore volume inpores having diameters less than about 70 Å, which process comprises:(a)titrating an aqueous solution of an acid aluminum salt selected from thegroup consisting of aluminum sulfate, aluminum nitrate and aluminumchloride, with an aqueous solution of a base in the presence of aphosphorus-containing compound at a pH in the range between about 5.5and about 8.0 and a temperature in the range between about 20° C. andabout 90° C., thereby forming a precipitate, (b) aging the precipitateat a temperature ranging from about 20° C. to about 90° C. for at leastabout 15 minutes at a pH ranging from about 8.0 to about 11.0, (c)washing the precipitate, (d) mixing the precipitate with one or moresolution(s) containing molybdate or dimolybdate salts and nickel saltsat a pH in the range between about 25° C. and about 100° C. untiladsorption of the salts onto the precipitate is sufficient to yield afinal catalyst having from about 2.5% w to about 4% w nickel and fromabout 10% w to about 14% w molybdenum, (e) partially drying the productof step (d) to reduce loss on ignition to between about 55% and about65%, (f) passing the product of step (e) through a mixing means, (g)extruding the product of step (f), and (h) drying and calcining theproduct of step (g) at a temperature ranging from about 300° C. to about900° C.
 100. A process for preparing highly active hydrotreatingcatalysts having surface areas at least about 300 m² /g, at least about20% of the pore volume in pores having diameters greater than about 350Å and at least about 20% of the pore volume in pores having diametersless than about 70 Å, which process comprises:(a) titrating an aqueoussolution of an acid aluminum salt selected from the group consisting ofaluminum sulfate, aluminum nitrate and aluminum chloride with an aqueoussolution of a base in the presence of a phosphorus-containing compoundat a pH in the range between about 5.5 and about 8.0 and a temperaturein the range between about 20° C. and about 90° C., thereby forming aprecipitate, (b) aging the precipitate at a temperature ranging fromabout 20° C. to about 90° C. for at least about 15 minutes at a pHranging from about 8.0 to about 11.0, (c) washing the precipitate, (d)mixing the precipitate with one or more solution(s) containing molybdateor dimolybdate salts and cobalt salts, and phosphoric acid in an amountof from about 0.2 to about 1.5 moles of phosphorus per mole ofmolybdenum at a pH in the range between about 4.0 and about 8.0 and atemperature in the range between about 25° C. and about 100° C. untiladsorption of the salts onto the precipitate is sufficient to yield afinal catalyst having from about 2.5% w to about 4% w cobalt and fromabout 10% w to about 14% w molybdenum, (e) partially drying the productof step (d) to reduce loss on ignition to between about 55% and about65%, (f) passing the product of step (e) through a mixing means, (g)extruding the product of step (f), and (h) drying and calcining theproduct of step (g) at a temperature ranging from about 300° C. to about900° C.
 101. A process for preparing highly active hydrotreatingcatalysts having surface areas at least about 300 m² /g, at least about20% of the pore volume in pores having diameters greater than about 350Å and at least about 20% of the pore volume in pores having diametersless than about 70 Å, which process comprises:(a) titrating an aqueoussolution of an acid aluminum salt selected from the group consisting ofaluminum sulfate, aluminum nitrate and aluminum chloride with an aqueoussolution of a base in the presence of a phophorus-containing compound ata pH in the range between about 5.5 and about 8.0 and a temperature inthe range between about 20° C. and about 90° C., thereby forming aprecipitate, (b) aging the precipitate at a temperature ranging fromabout 20° C. to about 90° C. for at least about 15 minutes at a pHranging from about 8.0 to about 11.0, (c) washing the precipitate, (d)mixing the precipitate with one or more solution(s) containing molybdateor dimolybdate salts and cobalt salts at a pH in the range between about4.0 and about 8.0 and a temperature in the range between about 25° C.and about 100° C. until adsorption of the salts onto the precipitate issufficient to yield a final catalyst having from about 2.5% w to about4% w cobalt and from about 10% w to about 14% w molybdenum, (e)partially drying the product of step (d) to reduce loss on ignition tobetween about 55% and about 65%, (f) passing the product of step (e)through a mixing means, (g) extruding the product of step (f), and (h)drying and calcining the product of step (g) at a temperature rangingfrom about 300° C. to about 900° C.
 102. A process for preparing highlyactive hydrotreating catalysts having surface areas at least about 300m² /g, at least about 20% of the pore volume in pores having diametersgreater than about 350 Å and at least about 20% of the pore volume inpores having diameters less than about 70 Å, which process comprises:(a)titrating an aqueous solution of an acid aluminum salt selected from thegroup consisting of aluminum sulfate, aluminum nitrate and aluminumchloride, with an aqueous solution of a base in the presence of aphosphorus-containing compound at a pH in the range between about 5.5and about 8.0 at a temperature in the range between about 20° C. andabout 90° C., thereby forming a precipitate, (b) aging the precipitateat a temperature ranging from about 20° C. to about 90° C. for at leastabout 15 minutes at a pH ranging from about 8.0 to about 11.0, (c)washing the precipitate, (d) mixing the precipitate with dry,water-soluble nickel salts, dry, water-soluble molybdate or dimolybdatesalts, and phosphoric acid in an amount of from about 0.2 to about 1.5moles of phosphorus per mole of molybdenum, at a pH in the range betweenabout 4.0 and about 8.0 and a temperature in the range between about 25°C. and about 100° C. to yield a final catalyst having from about 2.5% wto about 4% w nickel and from about 10% w to about 14% w molybdenum, (e)partially drying the product of step (d) to reduce loss on ignition tobetween about 55% and about 65%, (f) passing the product of step (e)through a mixing means, (g) extruding the product of step (f), and (h)drying and calcining the product of step (g) at a temperature rangingfrom about 300° C. to about 900° C.
 103. A process for preparing highlyactive hydrotreating catalysts having surface areas at least about 300m² /g, at least about 20% of the pore volume in pores having diametersgreater than about 350 Å and at least about 20% of the pore volume inpores having diameters less than about 70 Å, which process comprises:(a)titrating an aqueous solution of an acid aluminum salt selected from thegroup consisting of aluminum sulfate, aluminum nitrate and aluminumchloride, with an aqueous solution of a base in the presence of aphosphorus-containing compound at a pH in the range between about 5.5and about 8.0 at a temperature in the range between about 20° C. andabout 90° C., thereby forming a precipitate, (b) aging the precipitateat a temperature ranging from about 20° C. to about 90° C. for at leastabout 15 minutes at a pH ranging from about 8.0 to about 11.0, (c)washing the precipitate, (d) mixing the precipitate with dry,water-soluble nickel salts and dry, water-soluble molybdate ordimolybdate salts at a pH in the range between about 4.0 and about 8.0and a temperature in the range between about 25° C. and about 100° C. toyield a final catalyst having from about 2.5% w to about 4% w nickel andfrom about 10% w to about 14% w molybdenum, (e) partially drying theproduct of step (d) to reduce loss on ignition to between about 55% andabout 65%, (f) passing the product of step (e) through a mixing means,(g) extruding the product of step (f), and (h) drying and calcining theproduct of step (g) at a temperature ranging from about 300° C. to about900° C.
 104. A process for preparing highly active hydrotreatingcatalysts having surface areas at least about 300 m² /g, at least about20% of the pore volume in pores having diameters greater than about 350Å and at least about 20% of the pore volume in pores having diametersless than about 70 Å, which process comprises:(a) titrating an aqueoussolution of an acid aluminum salt selected from the group consisting ofaluminum sulfate, aluminum nitrate and aluminum chloride, with anaqueous solution of a base in the presence of a phosphorus-containingcompound at a pH in the range between about 5.5 and about 8.0 at atemperature in the range between about 20° C. and about 90° C., therebyforming a precipitate, (b) aging the precipitate at a temperatureranging from about 20° C. to about 90° C. for at least about 15 minutesat a pH ranging from about 8.0 to about 11.0, (c) washing theprecipitate, (d) mixing the precipitate with dry, water-soluble cobaltsalts, dry, water-soluble molybdate or dimolybdate salts, and phosphoricacid in an amount of from about 0.2 to about 1.5 moles of phosphorus permole of molybdenum, at a pH in the range between about 4.0 and about 8.0and a temperature in the range between about 25° C. and about 100° C. toyield a final catalyst having from about 2.5% w to about 4% w cobalt andfrom about 10% w to about 14% w molybdenum, (e) partially drying theproduct of step (d) to reduce loss on ignition to between about 55% andabout 65%, (f) passing the product of step (e) through a mixing means,(g) extruding the product of step (f), and (h) drying and calcining theproduct of step (g) at a temperature ranging from about 300° C. to about900° C.
 105. A process for preparing highly active hydrotreatingcatalysts having surface areas at least about 300 m² /g, at least about20% of the pore volume in pores having diameters greater than about 350Å and at least about 20% of the pore volume in pores having diametersless than about 70 Å, which process comprises:(a) titrating an aqueoussolution of an acid aluminum salt selected from the group consisting ofaluminum sulfate, aluminum nitrate and aluminum chloride, with anaqueous solution of a base in the presence of a phosphorus-containingcompound at a pH in the range between about 5.5 and about 8.0 at atemperature in the range between about 20° C. and about 90° C., therebyforming a precipitate, (b) aging the precipitate at a temperatureranging from about 20° C. to about 90° C. for at least about 15 minutesat a pH ranging from about 8.0 to about 11.0, (c) washing theprecipitate, (d) mixing the precipitate with dry, water-soluble cobaltsalts and dry, water-soluble molybdate or dimolybdate salts at a pH inthe range between about 4.0 and about 8.0 and a temperature in the rangebetween about 25° C. and about 100° C. to yield a final catalyst havingfrom about 2.5% w to about 4% w cobalt and from about 10% w to about 14%w molybdenum, (e) partially drying the product of step (d) to reduceloss on ignition to between about 55% and about 65%, (f) passing theproduct of step (e) through a mixing means, (g) extruding the product ofstep (f), and (h) drying and calcining the product of step (g) at atemperature ranging from about 300° C. to about 900° C.
 106. A processfor preparing highly active hydrotreating catalysts having surface areasat least about 300 m² /g, at least about 20% of the pore volume in poreshaving diameters greater than about 350 Å and at least about 20% of thepore volume in pores having diameters less than about 70 Å, whichprocess comprises:(a) titrating an aqueous solution of an acid aluminumsalt selected from the group consisting of aluminum sulfate, aluminumnitrate and aluminum chloride, with an aqueous solution of a base in thepresence of a phosphorus-containing compound at a pH in the rangebetween about 5.5 and about 8.0 at a temperature in the range betweenabout 20° C. and about 90° C., thereby forming a precipitate, (b) agingthe precipitate at a temperature ranging from about 20° C. to about 90°C. for at least about 15 minutes at a pH ranging from about 8.0 to about11.0, (c) washing the precipitate, (d) mixing a dry, water-solublemolybdate or dimolybdate salt and a mixture of a dry, water-solublenickel salt and phosphoric acid in an amount of from about 0.2 to about1.5 moles of phosphorus per mole of molybdenum with the precipitate at apH in the range between about 4.0 and about 8.0 and a temperature in therange between about 25° C. and about 100° C. to yield a final catalysthaving from about 2.5% w to about 4% w nickel and from about 10% w toabout 14% w molybdenum, (e) partially drying the product of step (d) toreduce loss on ignition to between about 55% and about 65%, (f) passingthe product of step (e) through a mixing means, (g) extruding theproduct of step (f), and (h) drying and calcining the product of step(g) at a temperature ranging from about 300° C. to about 900° C.
 107. Aprocess for preparing highly active hydrotreating catalysts havingsurface areas at least about 300 m² /g, at least about 20% of the porevolume in pores having diameters greater than about 350 Å and at leastabout 20% of the pore volume in pores having diameters less than about70 Å, which process comprises:(a) titrating an aqueous solution of anacid aluminum salt selected from the group consisting of aluminumsulfate, aluminum nitrate and aluminum chloride, with an aqueoussolution of a base in the presence of a phosphorus-containing compoundat a pH in the range between about 5.5 and about 8.0 at a temperature inthe range between about 20° C. and about 90° C., thereby forming aprecipitate, (b) aging the precipitate at a temperature ranging fromabout 20° C. to about 90° C. for at least about 15 minutes at a pHranging from about 8.0 to about 11.0, (c) washing the precipitate, (d)mixing a dry, water-soluble molybdate or dimolybdate salt and a mixtureof a dry, water-soluble cobalt salt and phosphoric acid in an amount offrom about 0.2 to about 1.5 moles of phosphorus per mole of molybdenumwith the precipitate at a pH in the range between about 4.0 and about8.0 and a temperature in the range between about 25° C. and about 100°C. to yield a final catalyst having from about 2.5% w to about 4% wcobalt and from about 10% w to about 14% w molybdenum, (e) partiallydrying the product of step (d) to reduce loss on ignition to betweenabout 55% and about 65%, (f) passing the product of step (e) through amixing means, (g) extruding the product of step (f), and (h) drying andcalcining the product of step (g) at a temperature ranging from about300° C. to about 900° C.
 108. A process for preparing highly activehydrotreating catalysts having surface areas at least about 300 m² /g,at least about 20% of the pore volume in pores having diameters greaterthan about 350° and at least about 20% of the pore volume in poreshaving diameters less than about 70°, which process comprises:(a)titrating an aqueous solution of an acid with an aqueous solution of abasic aluminum compound selected from the group consisting of sodiumaluminate and potassium aluminate in the presence of aphosphorus-containing compound at a pH in the range between about 5.5and about 8.0 and a temperature in the range between about 20° C. andabout 90° C., thereby forming a precipitate, (b) aging the precipitateat a temperature ranging from about 20° C. to about 90° C. for at leastabout 15 minutes at a pH ranging from about 8.0 to about 11.0, (c)washing the precipitate, (d) mixing the precipitate with one or moresolution(s) containing molybdate or dimolybdate salts and nickel salts,and phosphoric acid in an amount of from about 0.2 to about 1.5 moles ofphosphorus per mole of molybdenum at a pH in the range between about 4.0and about 8.0 and a temperature in the range between about 25° C. andabout 100° C. until adsorption of the salts onto the precipitate issufficient to yield a final catalyst having from about 2.5% w to about4% w nickel and from about 10% w to about 14% w molybdenum, (e)partially drying the product of step (d) to reduce loss on ignition tobetween about 55% and about 65%, (f) passing the product of step (e)through a mixing means, (g) extruding the product of step (f), and (h)drying and calcining the product of step (g) at a temperature rangingfrom about 300° C. to about 900° C.
 109. A process for preparing highlyactive hydrotreating catalysts having surface areas at least about 300m² /g, at least about 20% of the pore voIume in pores having diametersgreater than about 350 Å and at least about 20% of the pore volume inpores having diameters less than about 70 Å, which process comprises:(a)titrating an aqueous solution of an acid with an aqueous solution of abasic aluminum compound selected from the group consisting of sodiumaluminate and potassium aluminate in the presence of aphosphorus-containing compound at a pH in the range between about 5.5and about 8.0 and a temperature in the range between about 20° C. andabout 90° C., thereby forming a precipitate, (b) aging the precipitateat a temperature ranging from about 20° C. to about 90° C. for at leastabout 15 minutes at a pH ranging from about 8.0 to about 11.0, (c)washing the precipitate, (d) mixing the precipitate with one or moresolution(s) containing molybdate or dimolybdate salts and nickel saltsat a pH in the range between about 4.0 and about 8.0 and a temperaturein the range between about 25° C. and about 100° C. until adsorption ofthe salts onto the precipitate is sufficient to yield a final catalysthaving from about 2.5% w to about 4% w nickel and from about 10% w toabout 14% w molybdenum, (e) partially drying the product of step (d) toreduce loss on ignition to between about 55% and about 65%, (f) passingthe product of step (e) through a mixing means, (g) extruding theproduct of step (f), and (h) drying and calcining the product of step(g) at a temperature ranging from about 300° C. to about 900° C.
 110. Aprocess for preparing highly active hydrotreating catalysts havingsurfaCe areas at least one about 300 m² /g, at least about 20% of thepore volume in pores having diameters greater than about 350 Å and atleast about 20% of the pore volume in pores having diameters less thanabout 70 Å, which process comprises:(a) titrating an aqueous solution ofan acid with an aqueous solution of a basic aluminum compound selectedfrom the group consisting of sodium aluminate and potassium aluminate inthe presence of a phosphorus-containing compound at a pH in the rangebetween about 5.5 and about 8.0 and a temperature in the range betweenabout 20° C. and about 90° C., thereby forming a precipitate, (b) agingthe recipitate at a temperature ranging from about 20° C. to about 90°C. for at least about 15 minutes at a pH ranging from about 8.0 to about11.0, ranging from about 300° C. to about 900° C. (c) washing theprecipitate, (d) mixing the precipitate with one or more solution(s)containing molybdate or dimolybdate salts and cobalt salts, and aphosphoric acid in an amount of from about 0.2 to about 1.5 moles ofphosphorus per mole of molybdenum at a pH in the range between about 4.0and about 8.0 and a temperature in the range between about 25° C. andabout 100° C. until adsorption of the salts onto the precipitate issufficient to yield a final catalyst having from about 2.5% w to about4% w cobalt and from about 10% w to about 14% w molybdenum, (e)partially drying the product of step (d) to reduce loss on ignition tobetween about 55% and about 65%, (f) passing the product of step (e)through a mixing means, (g) extruding the product of step (f), and (h)drying and calcining the product of step (g) at a temperature rangingfrom about 300° C. to about 900° C.
 111. A process for preparing highlyactive hydroteating catalysts having surface areas at least about 300 m²/g, at least about 20% of the pore volume in pores having diametersgreater than about 350 Å and at least about 20% of the pore volume inpores having diameters less than about 70 Å, which process comprises:(a)titrating an aqueous solution of an acid with an aqueous solution of abasic aluminum compound selected from the group consisting of sodiumaluminate and potassium aluminate in the presence of aphosphorus-containing compound at a pH in the range between about 5.5and about 8.0 and a temperature in the range between about 20° C. andabout 90° C., thereby forming a precipitate, (b) aging the precipitateat a temperature ranging from about 20° C. to about 90° C. for at leastabout 15 minutes at a pH ranging from about 8.0 to about 11.0, (c)washing the precipitate, (d) mixing the precipitate with one or moresolution(s) containing molybdate or dimolybdate salts and cobalt saltsat a pH in the range between about 4.0 and about 8.0 and a temperaturein the range between about 25° C. and about 100° C. until adsorption ofthe salts onto the precipitate is sufficient to yield a final catalysthaving from about 2.5% w to about 4% w cobalt and from about 10% w toabout 14% w molybdenum, (e) partially drying the product of step (d) toreduce loss on ignition to between about 55% and about 65%, (f) passingthe product of step (e) through a mixing means, (g) extruding theproduct of step (f), and (h) drying and calcining the product of step(g) at a temperature ranging from about 300° C. to about 900° C.
 112. Aprocess for preparing highly active hydrotreating catalysts havingsurface areas at least about 300 m² /g, at least about 20% of the porevolume in pores having diameters greater than about 350 Å and at leastabout 20% of the pore volume in pores having diameters less than about70 Å, which process comprises:(a) titrating an aqueous solution of anacid with an aqueous solution of a basic aluminum compound selected fromthe group consisting of sodium aluminate and potassium aluminate, in thepresence of a phosphorus-containing compound at a pH in the rangebetween about 5.5 and about 8.0 at a temperature in the range betweenabout 20° C. and about 90° C., thereby forming a precipitate, (b) agingthe precipitate at a temperature ranging from about 20° C. to about 90°C. for at least about 15 minutes at a pH ranging from about 8.0 to about11.0, (c) washing the precipitate, (d) mixing the precipitate with dry,water-soluble nickel salts, dry, water-soluble molybdate or dimolybdatesalts, and phosphoric acid in an amount of from about 0.2 to about 1.5moles of phosphorus per mole of molybdenum, at a pH in the range betweenabout 4.0 and about 8.0 and a temperature in the range between about 25°C. and about 100° C. to yield a final catalyst having from about 2.5% wto about 4% w nickel and from about 10% w to about 14% w molybdenum, (e)partially drying the product of step (d) to reduce loss on ignition tobetween about 55% and about 65%, (f) passing the product of step (e)through a mixing means, (g) extruding the product of step (f), and (h)drying and calcining the product of step (g) at a temperature rangingfrom about 300° C. to about 900° C.
 113. A process for preparing highlyactive hydrotreating catalysts having surface areas at least about 300m² /g, at least about 20% of the pore volume in pores having diametersgreater than about 350 Å and at least about 20% of the pore volume inpores having diameters less than about 70 Å, which process comprises:(a)titrating an aqueous solution of an acid with an aqueous solution of abasic aluminum compound selected from the group consisting of sodiumaluminate and potassium aluminate, in the presence of aphosphorus-containing compound at a pH in the range between about 5.5and about 8.0 at a temperature in the range between about 20° C. andabout 90° C., thereby forming a precipitate, (b) aging the precipitateat a temperature ranging from about 20° C. to about 90° C. for at leastabout 15 minutes at a pH ranging from about 8.0 to about 11.0, (c)washing the precipitate, (d) mixing the precipitate with dry,water-soluble nickel salts and dry, water-soluble molybdate ordimolybdate salts at a pH in the range between about 4.0 and about 8.0and a temperature in the range between about 25° C. and about 100° C. toyield a final catalyst having from about 2.5% w to about 4% w nickel andfrom about 10% w to about 14% w molybdenum, (e) partially drying theproduct of step (d) to reduce loss on ignition to between about 55% andabout 65%, (f) passing the product of step (e) through a mixing means,(g) extruding the product of step (f), and (h) drying and calcining theproduct of step (g) at a temperature ranging from about 300° C. to about900° C.
 114. A process for preparing highly active hydrotreatingcatalysts having surface areas at least about 300 m² /g, at least about20% of the pore volume in pores having diameters greater than about 350Å and at least about 20% of the pore volume in pores having diametersless than about 70 Å, which process comprises:(a) titrating an aqueoussolution of an acid with an aqueous solution of a basic aluminumcompound selected from the group consisting of sodium aluminate andpotassium aluminate, in the presence of a phosphorus-containing compoundat a pH in the range between about 5.5 and about 8.0 at a temperature inthe range between about 20° C. and about 90° C., thereby forming aprecipitate, (b) aging the precipitate at a temperature ranging fromabout 20° C. to about 90° C. for at least about 15 minutes at a pHranging from about 8.0 to about 11.0, (c) washing the precipitate, (d)mixing the precipitate with dry, water-soluble cobalt salts, dry,water-soluble molybdate or dimolybdate salts, and phosphoric acid in anamount of from about 0.2 to about 1.5 moles of phosphorus per mole ofmolybdenum, at a pH in the range between about 4.0 and about 8.0 and atemperature in the range between about 25° C. and about 100° C. to yielda final catalyst having from about 2.5% w to about 4% w cobalt and fromabout 10% w to about 14% w molybdenum, (e) partially drying the productof step (d) to reduce loss on ignition to between about 55% and about65%, (f) passing the product of step (e) through a mixing means, (g)extruding the product of step (f), and (h) drying and calcining theproduct of step (g) at a temperature ranging from about 300° C. to about900° C.
 115. A process for preparing highly active hydrotreatingcatalysts having surface areas at least about 300 m² /g, at least about20% of the pore volume in pores having diameters greater than about 350Å and at least about 20% of the pore volume in pores having diametersless than about 70 Å, which process comprises:(a) titrating an aqueoussolution of an acid with an aqueous solution of a basic aluminumcompound selected from the group consisting of sodium aluminate andpotassium aluminate, in the presence of a phosphorus-containing compoundat a pH in the range between about 5.5 and about 8.0 at a temperature inthe range between about 20° C. and about 90° C., thereby forming aprecipitate, (b) aging the precipitate at a temperature ranging fromabout 20° C. to about 90° C. for at least about 15 minutes at a pHranging from about 8.0 to about 11.0, (c) washing the precipitate, (d)mixing the precipitate with dry, water-soluble cobalt salts and dry,water-soluble molybdate or dimolybdate salts at a pH in the rangebetween about 4.0 and about 8.0 and a temperature in the range betweenabout 25° C. and about 100° C. to yield a final catalyst having fromabout 2.5% w to about 4% w cobalt and from about 10% w to about 14% wmolybdenum, (e) partially drying the product of step (d) to reduce losson ignition to between about 55% and about 65%, (f) passing the productof step (e) through a mixing means, (g) extruding the product of step(f), and (h) drying and calcining the product of step (g) at atemperature ranging from about 300° C. to about 900° C.
 116. A processfor preparing highly active hydrotreating catalysts having surface areasat least about 300 m² /g, at least about 20% of the pore volume in poreshaving diameters greater than about 350 Å and at least about 20% of thepore volume in pores having diameters less than about 70 Å, whichprocess comprises:(a) titrating an aqueous solution of an acid with anaqueous solution of a basic aluminum compound selected from the groupconsisting of sodium aluminate and potassium aluminate, in the presenceof a phosphorus-containing compound at a pH in the range between about5.5 and about 8.0 at a temperature in the range between about 20° C. andabout 90° C., thereby forming a precipitate, (b) aging the precipitateat a temperature ranging from about 20° C. to about 90° C. for at leastabout 15 minutes at a pH ranging from about 8.0 to about 11.0, (c)washing the precipitate, (d) mixing a dry, water-soluble molybdate ordimolybdate salt and a mixture of a dry, water-soluble nickel salt andphosphoric acid in an amount of from about 0.2 to about 1.5 moles ofphosphorus per mole of molybdenum with the precipitate at a pH in therange between about 4.0 and about 8.0 and a temperature in the rangebetween about 25° C. and about 100° C. to yield a final catalyst havingfrom about 2.5% w to about 4% w nickel and from about 10% w to about 14%w molybdenum, (e) partially drying the product of step (d) to reduceloss on ignition to between about 55% and about 65%, (f) passing theproduct of step (e) through a mixing means, (g) extruding the product ofstep (f), and (h) drying and calcining the product of step (g) at atemperature ranging from about 300° C. to about 900° C.
 117. A processfor preparing highly active hydrotreating catalysts having surface areasat least about 300 m² /g, at least about 20% of the pore volume in poreshaving diameters greater than about 350 Å and at least about 20% of thepore volume in pores having diameters less than about 70 Å, whichprocess comprises:(a) titrating an aqueous solution of an acid with anaqueous solution of a basic aluminum compound selected from the groupconsisting of sodium aluminate and potassium aluminate, in the presenceof a phosphorus-containing compound at a pH in the range between about5.5 and about 8.0 at a temperature in the range between about 20° C. andabout 90° C., thereby forming a precipitate, (b) aging the precipitateat a temperature ranging from about 20° C. to about 90° C. for at leastabout 15 minutes at a pH ranging from about 8.0 to about 11.0, (c)washing the precipitate, (d) mixing a dry, water-soluble molybdate ordimolybdate salt and a mixture of a dry, water-soluble cobalt salt andphosphoric acid in an amount of from about 0.2 to about 1.5 moles ofphosphorus per mole of molybdenum with the precipitate at a pH in therange between about 4.0 and about 8.0 and a temperature in the rangebetween about 25° C. and about 100° C. to yield a final catalyst havingfrom about 2.5% w to about 4% w cobalt and from about 10% w to about 14%w molybdenum, (e) partially drying the product of step (d) to reduceloss on ignition to between about 55% and about 65%, (f) passing theproduct of step (e) through a mixing means, (g) extruding the product ofstep (f), and (h) drying and calcining the product of step (g) at atemperature ranging from about 300° C. to about 900° C.